alleryNumbers proportional to the direction cosines are called:
APosition vectors
BRectangular axes
CDirection ratios
DDirection cosines
Answer & Solution
Correct answer: C. Direction ratios
1. Multiplying each direction cosine by the length gives lr, mr and nr.
2. These numbers stay proportional to the direction cosines.
3. They are called the direction ratios, written as a, b and c.
_Source: syllabus Mathematics Part II, Chapter 10, Vector Algebra._
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